Sealant: seriously - what is reliable?

[UConnMel]

So my dad has a 220g that sprung a leak ~3 weeks ago. He has been spending the last 2 weeks trying to isolate said leak and it seems to be within the bottom 2" of the tank. He's gone to several LFS's and although none of them have an adequate amount of "aquarium approved" sealant in stock to seal an entire 220, almost every single one has given him the side story that they seal their customer's tanks with the GE brand at your local home depot/lowes. The one approved for windows, doors, etc. That seemed to be working ok. Was even able to fill his tank to the top, then drain, add sand, but when he started to fill again - low and behold it sprung a leak. GE customer service is now saying that the current formula is not safe for anything below water - basically acts like a sponge - soaks up the water, expands and separates. My question is: how are so many people still proposing to use this GE formula? I can tell you from first hand, it has been.... frustrating. To put it lightly. What is everyone else using that you have ABSOLUTE confidence in? My dad is devoid of motivation, maxed out on frustration, just wants to get to the point of starting over (which is sad enough in itself).

Any 100% endorsements out there? Both for tank integrity as well as reef safety?

 

[Diesel]

Silicone 1 will be your choice at the local stores.
But if you looking for the best and I say that as we talking 220 gallons and that's a lot of water on the floor you will be looking into this, best two strongest adhesives on the market are Momentive RTV 108 and SCS1200. RTV 108 has a Shear Strength of 200 psi, Tensile strength of 400 psi, and Peel Strength of 40 ppi. SCS1200 has a Shear of 110.8 psi, Tensile of 480 psi, and Peel of 61 ppi.

RTV108 = Clear
RTV103 = Black

SCS1201 = Clear
SCS1203 = Black

 

[UConnMel]

Silicone 1 will be your choice at the local stores.
But if you looking for the best and I say that as we talking 220 gallons and that's a lot of water on the floor you will be looking into this, best two strongest adhesives on the market are Momentive RTV 108 and SCS1200. RTV 108 has a Shear Strength of 200 psi, Tensile strength of 400 psi, and Peel Strength of 40 ppi. SCS1200 has a Shear of 110.8 psi, Tensile of 480 psi, and Peel of 61 ppi.

RTV108 = Clear
RTV103 = Black

SCS1201 = Clear
SCS1203 = Black

Thorough, as usual. Have you personally had any experience with the GE brand? He was using the GE silicone 1

 

[Diesel]

Thorough, as usual. Have you personally had any experience with the GE brand? He was using the GE silicone 1

For small tanks I've used the GE silicone 1 but 220 you better be save than sorry.
It also depends where it is leaking aa you might have to strip the whole tank, and I mean take all glass panels apart and start over.

 

[mfinn]

IMO just adding a new inside seal to a tank that large may not hold water for very long.
If the silicone that holds the 2 panes of glass together has failed, you need to pull it all apart and rebuild the tank.

For small tanks I've used the GE silicone 1 but 220 you better be save than sorry.
It also depends where it is leaking aa you might have to strip the whole tank, and I mean take all glass panels apart and start over.

I've seen several people try this in my area and the tank eventually leaks again.

 

[Diesel]

IMO just adding a new inside seal to a tank that large may not hold water for very long.
If the silicone that holds the 2 panes of glass together has failed, you need to pull it all apart and rebuild the tank.


I've seen several people try this in my area and the tank eventually leaks again.

Correct,
A tank that size I advice to hire a pro for this project.